2010 versus the 2000 consensus criteria in patients with normalised insulin-like growth factor 1 after transsphenoidal surgery has high predictive values for long-term recurrence-free survival in acromegaly.

Abstract

The present study investigated the factors associated with recurrence during long-term follow-up in acromegaly and compared the recurrence rate between patients in remission with 2010 vs 2000 consensus criteria. We retrospectively recruited 133 adult acromegalic patients who had undergone transsphenoidal surgery (TSS) from January 2013 to December 2014 and assessed their clinical characteristics, surgical outcomes and recurrence. Surgical remission was defined as normalised insulin-like growth factor 1 (IGF-1) with nadir growth hormone (GH) during an oral glucose tolerance test (OGTT) <1μg/L no less than 3months after TSS without adjuvant therapy. Recurrence was defined as persistently reelevated IGF-1 after surgical remission. Cox regression analysis and Kaplan-Meier survival analysis were performed to evaluate the factors associated with recurrence. Remission was achieved in 77 cases (57.9%) after TSS alone. Recurrence was seen in five cases (6.5%) at 12, 12, 12, 36 and 54months, respectively, after surgery. Cox regression analysis showed that a nadir GH<0.4μg/L (vs 0.4-1.0μg/L) at surgical remission (odds ratio [OR]=0.106; 95% confidence interval [CI]=0.017-0.645; P=0.015) and Ki-67 index (OR=2.636; 95% CI=1.023-6.791; P=0.045) were independent factors influencing recurrence. Kaplan-Meier survival analysis showed that the median recurrence-free survival was 36months (95% CI=20-52) for patients with nadir GH 0.4-1.0μg/L at surgical remission. The median recurrence-free survival for patients with nadir GH<0.4μg/L at surgical remission was much longer (ie, required further follow-up to estimate). A failure of GH suppression under 0.4μg/L during an OGTT in patients with normalised IGF-1 and a higher Ki-67 index are independent predictors of recurrence after surgical remission in GH-secreting pituitary adenomas. Compared to patients with nadir GH<0.4μg/L, those with nadir GH 0.4-1.0μg/L appear to have a significantly higher risk of recurrence.